In the title compound, [Ni(C17H14N3S2)2]·2C3H7NO, the Ni atom (site symmetry ) is N,S-chelated by two deprotonated Schiff base anions in a distorted square-planar geometry. The dihedral angle between the aromatic ring planes within the ligand is 86.37 (13)°. In the crystal structure, an N-HO hydrogen bond links the complex to the dimethylformamide solvent molecule.

Benzyl (1H-indol-2-ylmethylene)hydrazinecarbodithioate ethanol
hemisolvate (2 mmol, 0.65 g) was dissolved in ethanol (30 ml) along with
several drops of triethylamine. To the resulting
clear solution was added an ethanol
solution (10 ml) containing 1 mmol (0.25 g) of nickel acetate tetrahydrate.
The mixture was heated for an hour. The product that separated was
recrystallized from DMF to yield brown blocks of (I).

Fig. 1. View of (I) at the 70%
probability level. Hydrogen atoms are drawn as spheres of arbitrary radius.
The unlabelled atoms are generated by the symmetry operation (1–x, 1–y, 1–z)
and the hydrogen bonds are shown as dashed lines.